Garruk, Cacciatore Primitivo

For Garruk’s second ability, the greatest power among creatures you control is determined when that ability begins resolving.

For Garruk’s third ability, the number of Wurm tokens you put onto the battlefield is determined when that ability begins resolving.

If the greatest power among creatures you control is 0 or less, you’ll draw no cards. You won’t discard any cards this way.